Heat insulating coupling



May 16, 1939. R. H. GODDARD 2,158,182

' HEAT INSULATING COUPLING I Original Filed Aug. 51, 1934 L/ l/ l 1-'IIIIIII E II'II/ y ll 2 Dig //IIIIIII1 S Fade/t1. ai'dari KLAQMPatented May 16, 1939 UNITED STATES PATENT OFFICE 2,158,182 HEATINSULATING COUPLING Robert H. Goddard; Roswell, N. Mex.

Oiiginal application August 31, 1934, Serial No.

742,251, new Patent No. 2,127,865, dated August 23, 1938. Divided andthis application December 20, 1937, Serial No. 180,783

1 Claim.

perature operations may be disturbed, and if the bearings areexcessively cooled, lubrication of the bearings will be less effective.

It is the object of my invention as defined in this divisionalapplication to provide an improved heat-insulating coupling adapted forgeneral application and particularly designed for use in low-temperaturepumping apparatus.

My invention further relates to arrangements and combinations of partswhich will be hereinafter described and more particularly pointed outinthe appended claim.

A preferred form of the invention is shown in the drawing, in which Fig.1 is a front elevation of my improved coupling, with portions of anassociated centrifugal pump shown in section, and

Fig. 2 is an enlarged sectional front elevation of the coupling.

Referring particularly to Fig. 1, I have shown a portion of acentrifugal pump comprising a casing 20, an enclosed impeller 2|, animpeller shaft 22, and a supporting or drivingshaft 23 for saidimpeller, said shaft 23 being rotatably mounted in a bearing '25.

For the purpose of preventing heat transfer between the shafts 22 and23, these shafts are connected by a special heat-insulating couplingconstructed as follows:

A disc 26 is threaded on one end of the im peller shaft 22 and a similardisc 21 is threaded on the adjacent end of the supporting shaft 23. Thediscs 26 and 21 are connected by circumferentially spaced bolts 28, eachprovided with a sleeve 29, washers 30 and a collar 3|, all of suitablenon-conducting and heat-insulating material. By this construction anytransfer of heat generated by the shaft 23 in its bearing 25 to theimpeller shaft 22 is prevented, and excessive cooling of the bearing 25by the low temperature liquid in the pump is also prevented.

If a second supporting or driving shaft and bearing are used at theopposite side of the pump, a second coupling of similar heat-insulatingconstruction will be provided.

A centrifugal pump may thus be rendered capable of pumping liquidshaving very low boiling points and at temperatures much below thetemperature of the atmosphere in which the pump operates.

Attention is particularly called to the fact that all metal-to-metalcontact between the bolts 28 and the-discs 26 and 21 is avoided, whichis a matter of great importance. If any of the insulating members 29, 30or 3| are omitted, so

metal-to-metal contact is established, heat will be transferred throughsuch contact.

The advantages of the invention may b in part retained if the bolts 28are heat-insulated from one flange 26 or 21 only, but insulation of thebolts 28 from both, flanges as described has been found more eillcientand satisfactory.

Having thus described my invention and the advantages thereof, 1. do notwish to be limited to the details herein disclosed, otherwise than asset forth'in the claim, but what I claim is:

A heat-insulating driving coupling for connecting adjacent co-axialrotating members comprising a disc mounted on the end of one rotatingmember, a second disc mounted on the adjacent end of the second rotatingmember but spaced from said first member, clamping bolts connect: ingsaid discs, and heat-insulating means for said bolts and discscomprising sleeves for said bolts in said discs, spacing collars betweensaid discs and concentric with said bolts and sleeves, and washersbetween the ends of said bolts and said discs, said sleeves, collars andwashers all being of heat-insulating material and each sleeve extendingthrough both discs and through an interposed collar.

. ROBERT H. GODDARD.

